A lot of people load up SDXL in ComfyUI, slap on a ControlNet, hit generate, and ten seconds later their VRAM explodes. SDXL is way more resource-hungry than SD1.5—pick the wrong card and you’re either getting OOM every day or it’s so slow you wanna smash your keyboard. Here’s some real-world testing: a basic SDXL image at 1024 resolution uses about 6.
5G VRAM, each extra ControlNet adds 1.5 to 2.5G, upscalers pile on another 1 to 2G, and it stacks up fast. So if you want a smooth experience, 16G is the sweet spot—enough headroom for basic generation, single-layer ControlNet without choking VRAM, Tile upscaling or ESRGAN can handle it, and you can even train some LoRAs on the side.
At that price point, a few cards are within reach, and the 4070 Ti Super is one of the best bang-for-buck options. Don’t just look at whether it can run—SDXL workflows stack up, so leave enough buffer so you don’t run out of VRAM mid-generation.